Studies on animals'knowledge of resource locations are diverse. Animals use visual landmarks and spatial relations among landmarks to discriminate places where they found or stored food in the past (primates: Menzel &Juno 1985, MacDonald et al. 1994, Janson 1998, 2000;nonprimate mammals: Collett et al. 1986, Olton 1978, Vander Wall 1991, Jacobs 1992;birds: Sherry 1984;Shettleworth 1995;Krebs et al. 1990, Vander Wall 1990, Balda &Kamil 1992, Herz et al. 1994;insects and other animals: Gallistel 1990;Wehner et al., 1996). The travel patterns of primates suggest animals retain information about the location of resources. Tamarins move in neariy straight lines from one fruit-bearing tree to another tree of the same, synchronously fruiting species (Garber 1989). Chimpanzees transport stones hundreds of meters to tree-root anvils for cracking nuts (Boesch &Boesch 1984), and captive bonobos and orangutans will select, transport, and save tools to use 1 hour later (Mulcahy &Call 2006). Hamadryas baboons orient toward the distant waterhde at which the band will reassemble later (Sigg &Stolba 1981). The PI provided an experimental demonstration of the operation of learning and memory capabilities in wild primates. Japanese macaques appeared to form hypotheses about active food sites from one food find, taking into account the type of food item and the locations that contained it in past seasons (Menzel 1991). Captive long-tailed macaques varied their search according to food's proximity to visible environmental features (Menzel 1996a, b) and the spatial layout of initial food items (Hemmi &Menzel 1995). In studies of captive chimpanzees (E.Menzel 1973a,b, 1978, 1984), a single animal from a group of six was carried and could watch as an experimenter hid up to 18 piles of food in a 1-acre field. When the animal was released several min later, it recovered most of the hidden food. Its route connecting the food piles approximated a least-distance routing.